In-Depth Look: The South Korea Constitutional Court’s Decision on Climate Litigation

The South Korea Constitutional Court issued its decision on four consolidated climate litigation cases on 29 August 2024. In all cases, complainants argued that the South Korean government infringes on constitutionally protected fundamental rights by failing to adequately address the climate crisis.

Due to the similar subject matter of the four cases, the Constitutional Court consolidated them on 15 February 2024. Subsequently, hearings were held on 23 April and 21 May. Following a brief recap of the legal framework and the four original complaints, this article will discuss the ruling of the Constitutional Court in more detail.

Legal Framework

South Korea’s legal framework on climate change has evolved significantly in recent years. Currently, the legal framework under the Framework Act on Carbon Neutrality and Green Growth (the “Carbon Neutrality Framework Act” or “CNFA”) and its accompanying Enforcement Decree outlines South Korea’s approach to achieving its 2030 greenhouse gas (GHG) reduction targets. The Carbon Neutrality Framework Act was implemented on 24 September 2021. Article 8(1) CNFA mandates the government to set national mid- and long-term GHG reduction targets, including a specific target of reducing emissions by at least 35% from 2018 levels by 2030.

Article 3(1) of the current Enforcement Decree sets this reduction target at 40%. Additionally, the 1st National Plan for Carbon Neutrality and Green Growth, established in April 2023, details sectoral and annual GHG reduction targets for 2023-2030 to meet the national reduction goals as required under the CNFA. These targets serve as an administrative plan that outlines specific GHG emissions and removal figures by sector and year, in line with the overall reduction strategy set by the CNFA.

The cases also refer to South Korea’s previous Framework Act on Low Carbon, Green Growth (the “Old Green Growth Act”) and its accompanying Enforcement Decree (including several amendments). The Old Green Growth Act and old Enforcement Decree were repealed and replaced by the CNFA and new Enforcement Decree. Specifically, reference is made to Article 42(1) of the Old Green Growth Act, which is essentially the same as Article 8(1) CFNA.

Recap: What Were South Korea’s Four Climate Cases About?

Complainants in all four cases argue that climate change, driven by anthropogenic GHG emissions, poses severe threats to ecosystems, human health, social stability, and economic activities across the world, including in South Korea. International agreements such as the Paris Agreement mandate limiting global temperature rise to 1.5C to 2C above pre-industrial levels, requiring countries to adhere to their fair share of the global carbon budget. The complainants argue that current reduction targets shift the burden of GHG reduction onto future governments and generations, failing to meet the minimum requirements for fair distribution. They also assert that the legal framework is improperly delegating the setting of national GHG reduction targets to the executive branch, without legislative guidance.

Case 1: Do-Hyun Kim et al. v. South Korea (2020)

The first of the four climate cases was filed in 2020, when a group of 19 youths, all part of Youth4Climate Action, filed a constitutional complaint alleging that South Korea’s policies and laws on climate change violate their fundamental rights. This case, Do-Hyun Kim et al. v. South Korea, was a first-of-its-kind climate lawsuit in South Korea. The case initially argued that a 2019 amendment to Article 42(1)1 of the country’s Old Green Growth Act was unconstitutional. Under Article 42(1)1, the South Korean government was obligated to set medium- and long-term targets for the reduction of GHG emissions. Article 42(1)1 of the Old Green Growth Act was supplemented by an Enforcement Decree to set these precise targets (in Article 25(1). The disputed amendment had reduced South Korea’s emission reduction target to 24.4% compared to 2017 levels.

The youth argued that this target was too low to effectively guarantee the protection of their fundamental rights. Specifically, they claimed violations of their fundamental rights to life and pursuit of happiness (Article 10), their right to a healthy and pleasant environment (Article 35(1)), and their right to equality as opposed to older generations (Article 11).

On 16 February 2022 and 8 June 2022, the complainants added new claims following the replacement of the Old Green Growth Act with the Carbon Neutrality Framework Act. The claims then extended also to Article 8(1) CNFA and Article 3(1) of the accompanying updated Enforcement Decree.

Case 2: Byung-In Kim et al. v South Korea (2021)

A second case was filed by a group of over 100 plaintiffs against the South Korean government in 2021. The group argued that Article 8(1) CNFA violates their fundamental rights. Under Article 8(1) CFNA, the government is required to set a medium- to long-term reduction target, which should be 35% or higher by 2030, as compared to 2018 emission levels. However, the complainants argue that this target is not appropriate, not based on international agreements, and cannot protect their fundamental rights. This case also referenced Articles 10, 11, and 35(1) of the South Korean constitution. Other cited infringements of fundamental rights included Article 23 (right to property) and Article 34(6) (state obligation to prevent disasters).

Case 3: Woodpecker v South Korea (2022)

Next was the notable ‘foetus climate case’, in which a group of young plaintiffs, including an unborn foetus, filed a constitutional complaint regarding Article 3(1) of the Enforcement Decree of the Carbon Neutrality Framework Act. The plaintiffs in this case argued that Article 3(1) of the Enforcement Decree violates their fundamental rights, as the 40% reduction target is insufficient to protect their lives and safety from climate disasters and is not aligned with the Paris Agreement. The complainants in Woodpecker v. South Korea cited the same fundamental rights violations as in Byung-In Kim et al. v. South Korea. The plaintiffs requested a constitutional review of the target set under the applicable Enforcement Decree.

Case 4: Min-A Park v South Korea (2023)

Finally, the most recent case that is part of the consolidated ruling was brought by a group of 51 Koreans, who alleged that the government fails to provide protection of fundamental rights as required under the constitution. This case took a slightly different approach than its three predecessors. The alleged failure stems from South Korea’s 1st Carbon Neutrality Plan, which outlines the country’s emission reduction strategy to implement the 2030 targets. Here, it is not the 40% targeted reduction itself that is at stake, but rather the likely failure of the Carbon Neutrality Plan to achieve such a reduction. The complainants argued that even if the Carbon Neutrality Plan was implemented successfully, it would achieve a mere 29.6% emission reduction.

Climate Litigation Before the South Korea Constitutional Court

Article 8(1) CNFA

In considering the impact of climate change on fundamental rights, the Constitutional Court of South Korea reasoned that the Constitution’s Article 35(1) right to a healthy and pleasant environment extends to both the natural and living environments, which are at risk due to dangerous climate change. Hence, it is the government’s duty to “address the climate crisis by taking measures to mitigate such risks” through effective mitigation and adaptation measures. These measures must be “appropriate and effective” with regard to protected rights, based on scientific and international consensus. The Constitutional Court thus reviewed the appropriateness and effectiveness of the current legal framework in addressing climate change against scientific and international standards. This involved an examination of whether (i) South Korea’s GHG reduction target fairly aligns with global efforts; (ii) the target-setting framework avoids excessive future burdens, and (iii) it effectively ensures GHG reductions.

The Court concluded that Article 8(1) CNFA fails to provide a quantitative framework for emission reductions for the period of 2031 to 2049. Article 8(1) CNFA does not account for potential shortfalls beyond 2030, thereby shifting an excessive burden towards the future. Moreover, by not including a minimum emission reduction target for the period 2031-2049, the CNFA leaves this matter open to the executive branch, which the Court holds violates the principle of parliamentary reservation (e.g. certain important matters must be regulated by law passed by the legislature, rather than by executive orders). As per the Constitutional Court’s reasoning, this means that Article 8(1) CNFA is indeed not appropriate in addressing the risk of the climate crisis. It is thus infringing on complainants’ right to a healthy and pleasant environment. However, because Article 8(1) sets the minimum emission reduction target for 2030, the Court cannot have the section lose its effect altogether by issuing an unconstitutionality order. The Court therefore states that Article 8(1) is nonconform to the Constitution and must be amended by 28 February 2026 at the latest.

Article 3(1) of the Enforcement Decree of the CNFA

The Constitutional Court states that the only purpose of Article 3(1) of the Enforcement Decree of the CNFA is to set and implement a reduction target for 2030, in line with the specifications of the CNFA. Therefore, Article 3(1) of the Enforcement Decree of the CNFA cannot be said to violate any fundamental rights of the complainants.

1st National Plan for Carbon Neutrality and Green Growth

Finally, the Constitutional Court considered the allegations in Min-A Park v South Korea regarding sectoral and annual reduction targets laid down in the 1st National Plan for Carbon Neutrality and Green Growth. A majority of the justices, five out of nine, agreed that South Korea’s practice of using gross emissions of the base year compared to net emissions in a target year violates complainants' fundamental right to a healthy environment and is therefore unconstitutional. However, a minimum of six justices is required to affirm an unconstitutionality complaint.

Regarding the government’s financial plans, the Constitutional Court held that these were expressions of a long-term budget rather than immediate exercises of public power affecting fundamental rights.

Commentary

The South Korean Constitutional Court has critically addressed the perceived inadequacies of these targets and their implications for fundamental rights. While the Court identified constitutional issues with Article 8(1) CNFA, its decision ultimately stopped short of providing a comprehensive remedy for the complainants’ grievances.

The Court’s recognition of the climate crisis and its effect on fundamental rights is key here. Specifically, the Court highlighted the lack of a quantitative framework for emissions reductions beyond 2030 and the insufficient legislative guidance on how to handle potential shortfalls. However, the Court’s decision to uphold the existing targets and financial plans without substantial modifications may be seen as a partial response that does not fully align with the complainants’ demands for more stringent and immediate action.

The Court's ruling highlights a fundamental tension between judicial oversight and legislative flexibility. While the Court’s directive to amend the CNFA by February 2026 is a step towards aligning the law with constitutional standards, it does not directly address the immediate need for more ambitious and effective climate action. The ruling's impact on future climate litigation remains uncertain, and it may well necessitate further legal challenges if the legislative changes do not meet the evolving demands of the climate crisis.